Electrotherapy in mice: dopaminergic and noradrenergic effects in the Tail Suspension Test

The Tail Suspension Test (TST) is a psychotropic screening test which is used principally to detect antidepressant activity. Electrotherapy (ECT) is used to treat depressions which are resistant to the usual antidepressant drugs and has proved to have a profile in the TST approaching that of antidepressants after treating mice at the rate of 2 shocks per day for 5 days. The results of a single treatment were not statistically different from those of the control group, whereas single daily treatment for 5 days showed a reduction in immobility which did not differ significantly from the control group. The reduction in immobility, induced by 5 days of ECT treatment twice daily, was antagonized by sulpiride and prazosin but not by yohimbine, methysergide, metergoline and DL propranolol. The results suggest that electrotherapy leads to an increase in noradrenergic and dopaminergic activities expressed by a reduction in immobility in the TST.